Orchids are largest and most diverse group among
angiosperms. They are cultivated for beautiful flowers. They are widely known
their economic importance but less for medicinal value. Some plants like Dendrobiumcrumenative,
Eulophiacampestris,
Orchislatifolia,
Vandaroxburghii
and Vandatessellata
have been documented for their medicinal value..Phytochemically some orchids have been reported to
contain alkaloids, triterpenoids, flavonoids and stilbenoids. Ashtavarga (group of eight medicinal plants) is vital
part of Ayurvedic formulations like Chyvanprasha and four plants viz,
Riddhi, Vriddhi, Jivaka and Rishbhaka have been
discussed as possible members of family Orchidaceae.
Recently there has been tremendous progress in medicinal plants research;
however orchids have not been exploited fully for their medicinal
application. The article reviews medicinally important orchids along with
recent pharmacological investigations.

Key words: Orchids,Orchidaceae,Medicinal Plants,Ayurveda

Introduction

Orchidaceae is one of the largest families among
angiosperms. According to one estimate the family includes 800 genera and
25,000 species ( 1 ). Orchids are well known for
there economic importance and widely cultivated for ornamental purposes.
Orchids are cosmopolitan in distribution. Vanilla planifolia
is commercially important orchid as it is source of vanillin used as a
foodstuff flavoring ( 2 ).

Historical aspects

The
term orchid was coined by Theophrastus as anatomy of the plants resemble with
testicles. Greek word orchid literally means testicles ( 1
). This may account for use of orchids
as aphrodisiacs in ancient civilizations. When we study the history of
ancient alternative systems of medicine Ayurveda
and Traditional Chinese Medicine (TCM) are
on the forefront ( 3 ).

Traditional Chinese medicine widely utilizes orchids in medicines. A
few of them have been subjected to phytochemical
and pharmacological studies ( 3). In India
wok has been carried out on chemical analysis of some medicinally useful
orchids. Eulophiacampestris,
Orchislatifolia,
Vandaroxburgiiare some important plants to mention ( 39 ). Dendrobiummacraei
is another important orchid from Ayurvedic point of
view as it is reported to be source of Jivanti. (6)
Cypripedium parviflora is widely used as
aphrodisiac and nervine tonic in Western Herbalism( 1 ;3).

Asthavarga is important ingredient of various classical Ayurvedic formulations like Chavyanprasa
(4). Out of eight constituents of Ashtavarga, four have been reported to be orchids (Table
1.). Table 1 shows eight medicinal plants used in Ashtavarga, composite Ayurvedic
formulation. The plants marked with stars have been reported to be orchids.

Table 1. Medicinal plants used in Ashtavarga

S.No.

Ayurvedic
name

Botanical name

Family

Part used

1.

Jivaka*

Malaxismuscifrea

Orchidaceae

Bulb

2.

Rishbhaka*

Malaxis acuminate

Orchidaceae

Pseudo-bulb

3.

Meda

Polygonumverticilliatum

Polygonaceae

Rhizome

4.

Mahameda

Polygonumcirrifolium

Polygonaceae

Rhizome

5.

Kakoli

Roscoeaprocera

Zingiberaceae

Root

6.

KshiraKakoli

Fritillariaroyeli

Liliaceae

Root

7.

Riddhi*

Habenariaintermedia

Orchidaceae

Root

8.

Vriddhi*

Habenariaedgeworthii

Orchidaceae

Root

Many
medicinal orchids are reported to contain alkaloids. Antimicrobial activities
of some orchids have been suggested although detailed investigations are
still warranted. (7) Recent works have reported isolation of anthocyanins, stilebnoids and triterpenoids from orchids. Orchinol,
hircinol, cypripedin, jibantine, nidemin and loroglossin are some important phytochemicals
reported from orchids. Some of the phytochemicals
isolated from orchids along with biological source have been tabulated in Table
2.

Botany:Arundinagraminifolia
is a large terrestrial plant with erect stems that are 1.5-2.5 cm tall and up
to 1.5 cm in diameter. The leaves are borne in two ranks and are narrowly
oblong and grass-like, 12-30 cm long and 1.6-2.5 cm. The simple, terminal
inflorescence may be branched and is 15-30 cm long. The large cattleya-like flowers are purple-red, flesh-coloured or white and are up to 10 cm across. The lip is
darker than the sepals and petals, often veined darker purple and has a
yellow to orange-yellow patch at the base. The short-lived, scented flowers
last for about 3 days and there are usually several open at a time. (18)

Botany: Dactylorhizahatagirea
is a terrestrial orchid with fleshy tuberous roots. Tubers are slightly
flattened, palmately lobed. Stem is usually 30-50
cm tall, leafy and with few sheathing scales in the lower portion. Leaves are
erect, oblong-lanceolate, 7-15 cm long, obtuse and
with a sheathing base. Flowers are pink-purple, crowded in terminal, spicate racemes (26).

Parts used:
Roots.

Phytochemistry: Mucilage,
starch, glucoside: loroglossin,
albumen, volatile oil and ash (25). Five new compounds known as dactylorhins A-E and two natural compounds known as dactyloses A-B have been reported from plant growing in Nepal
(27).

Therapeutics:
In Vietnam
the plant is used in the treatment of pulmonary tuberculosis, general
debility, flatulence, dyspepsia, reduced salivation, parched and thirsty
mouth, night sweats, fever and anorexia (30).

Pre-clinical
studies: Anti-mutagenic (28).

EulophianudaLindl.

Syn: Eulophiadabia (D.Don) Hochr

Common
name: Whitton root, Salep.

Ayurvedic name: Mankand.

Distribution:
Himalayas.

Botany: The
tubers, conical, surrounded with circular marks. The remains of leaflets,
yellowish white or of a green colour.

Parts used:
Tubers.

Phytochemistry: Phenanthrenes: chief is nudol
(31, 32).

Actions: Demulcent and anthemnintic.

Therapeutics: Worm infestation and scrofula.

Eulophiacampestris Wall. Ex Stapf

Syn: Eulophiadabia (D.Don) Hochr

Distribution:
Himalayas.

Botany: The
tubers, conical, surrounded with circular marks. The remains of leaflets,
yellowish white or of a green colour.

Therapeutics:
Paste of leaves is used as application in fevers. It is ingredient of

RasnaPanchakaQuatha, Ayurvedic formulation used in the treatment of arthritis
and rheumatism. Expressed juice of the leaves is sued in the treatment of otitismedia.The root is used
as antidote against scorpion sting and remedy for bronchitis (26).